Zigzag sewing mechanism



' Feb. 16, 1943.

J. GALKIN ZIG-ZAG SEWING MECHANISM Filed July 27, 1940 7 Sheets- Sheet 1ED N . INVEN TOR.

ATTORNEY.

SEPH GALKIN Feb. 16, 1943. J.-GALKIN 2,311,222

ZIG-ZAG SEWING MECHANISM y I I Filed July 27', 1940 7 sheet -sheet 2- tv JOSEPH GALKIN g; INVENTOR.

ATTORNEY.

Feb. 16, 1943. J. GALKIN 2,311,222

ZIGv-ZAG szwxue MECHANISM Fil ed July 27, 1949 7 Sheets-Sheet s Fig-9JOSEPH GALKIN I NV EN TOR.

BY W AW) ATTORNEY.

Feb. 16, 1943. J. GALKIN 2,311,222

zxe-zae SEWING MECH-ANISM Filed July 27, 1940 7 Sheets-Sheet e V g; 3 56v w I 1 I an 1 N I '5 :2

| la I JOSEPH GALRIN 2 INVENTOR m mm BYWM

Feb. 16, 1943. J, N' 2,311,222

ZIG-ZAG SEWING MECHANISM Filed July 2?, 940 7 Sheets-Sheet 7 JOSEPHGALKIN "INVENTOR ATTORNEY Patented Feb. 16, 1943 UNITED STATES harem"OFFICE ZIGZAG SEWING MECHANISM Joseph Galkin, New York, N. Y.

Application July 27, 1940, Serial No. 348,034

Claims.

meshed engagement with a driven gear rotatably mounted below the worksupporting base of the sewing machine, the driven gear shaft having anadjustable eccentric secured thereto and having a vibratable connectionfor imparting reciprocating motions to a slidably mounted feed-dogcarrier and feed-dog and to the needle plate.

Another object of this invention is to provide means connecting theneedle plate and the feeddog carrier for simultaneous to-and-fromovement, when the feed-dog is moved to-and-fro, the said connectingmeans being positioned to one side of the feed-dog so as to providefeeding teeth at the front and rear of the central portion of thefeed-dog and on opposite sides of the needle.

Another object of this invention is to provide a vibratable connectionfor imparting high speed up and down, and sideways, and forward andbackward motions of the feed-dog and needle plate.

Another object of this invention is to provide a cam having a shapewhich will cause momentary cessation of the transverse motions at eachend of said motions.

Another object of this invention is to'providein combination with saidmomentary cessation cam and with said direct high speed drive, aneedle-throat for centralizing the bobbin thread and to prevent breakageof said thread when very wide transverse movements are made by theneedle.

This application is a continuation in part of my copending, abandonedapplication, Serial No. 281,471, filed June 27, 1939.

With the above and other objects in view, the invention will behereinafter more particularly described, and the combination andarrangement of parts will be shown in the accompanying drawings andpointed out in the claims which form part of this specification.

Reference will now be had to the drawings, wherein like numerals ofreference designate corresponding parts throughout the several views, inwhich: I

Figure 1 is a side elevation of the improved zig-zag stitching machine.

Figure 2 is a bottom plan view.

Figure 3 is a top plan view of the needle plate slidably mounted in acloth plate.

Figure 4 is a cross-sectional view, the section being taken as on line4-4 in Figure 3.

Figure 5 is a cross-sectional View, the section being taken as on line55 in Figure 6, and showing a thread control arm having an aperture forthe bobbin thread in alignment with the needle.

Figure 6 is a fragmentary plan View of the sewing machine having thezig-zag mechanism applied thereto.

Figure 7 is a cross-sectional view, the section being taken as on line11 in Figure 6.

Figure 8 is a plan view of the adjustable eccentric for adjusting thewidth of the zig-zag stitches.

Figure 9 is a cross-sectional view of the eccentric, the section beingtaken as on line 99 in Figure 8.

Figure 10 is a top plan view of a work supporting plate having anaperture centrally thereof for a needle-throat.

Figure 11 is a cross-sectional view similar to Figure 5, and showing theneedle-throat extending upwardly to the upper surface of the worksupporting plate.

Figure 12 is a bottom plan view of a sewing machine showing a modifiedzig-zag mechanism comprising a heart-shaped cam.

Figure 13 is an enlarged fragmentary plan view of the modified zig-zagmechanism shown in Figure 12, a bearing bracket being broken away toshow a full view of the cam.

Figure 14 is a side view of the modified zig-zag mechanism shown inFigures 12 and 13.

In the illustrated embodiment of the invention, shown in Figures 1 to11, inclusive, the numeral Ii) indicates a sewing machine comprising abase-plate H, and an overhanging arm l2 having a head I 3 at its freeend. A main actuating shaft l4 mounted in the arm l2 through suitableconnections imparts vertical reciprocatory movements to the needle-bar15 whereby the needle I6 is reciprocated once for every rotation of themain shaft l4.

Secured to the base-plate H is a cloth plate I! having a guideway I8,preferably of dovetail form and positioned transversely of the line ofstitching. The cloth plate I? has a rectangularly shaped aperture 19 inalignment with the guideway. An elongated needle plate 20 havcrank arms32, 32.

ing two beveled side edges to fit into the guide- Way 13, has beenslidably mounted in said guideway and has a stud 39 extending downwardlytherefrom and passing through the aperture i9 below the cloth plate IT.

The needle plate has a needle opening and feed slots for a feed-dog 22,the needle being timed to cooperate with a hook or loop-taker 23 for thepurpose of forming stitches, the hook being driven by a shaft 24. Apresser-foot bar 25 is yieldably supported in the head l3 and carries apresser-foot 26 supported solely for up and down movements, as is wellknown in the art.

The feed-dog 22 has teeth formed therein by intersecting grooves whichare positioned in right-angular relation to each other. The teeth 33 arepyramid-shaped.

As shown in Figures 6 and 7, the feed-dog 22 is fastened to the feed-dogcarrier 2'? which comprises an elongated end portion 23 having a throughcylindrical opening 29 for sliding engagement with a spindle 30. Thespindle 3D is supported in offset relation from the rock-shaft 3| as iswell known in the art.

The elongated portion 28 of the feed-dog carrier 21 may be slidablymounted on the spindle 30 as shown, or the spindle may be fastened tothe carrier 21 and be slidably mounted in the The rock-shaft 3|functions to produce the back-and-forth movements of the feed-dogcarrier 21 and the feed-dog 22 in conventional manner.

The up-and-down movements of the feed-dog 22 are produced by arock-shaft having an integral crank arm 36 which carries a guide pin orspindle 31.

For the purpose of my invention, which is to provide an extremely simplemechanism for moving the feed-dog carrier and feed-dog and needle platetransversely of the line of stitching at high speed, I have formed anelongated through opening 38 in the feed-dog carrier 2! and haveprovided a stud 39 integral with and projecting from the lower surfaceof the needle-plate. In assembled relation the stud 39 passes throughthe clearance aperture l9 in the cloth plate I1 and engages with thewalls of the slot 38 in the feed-dog carrier 21. In this assembledrelation, when the feed-dog is moved transversely the needle-plate issimultaneously moved transversely by the feed-dog.

I have secured a drive gear 45 on the hook driving shaft 24 closelyadjacent to the forward bearing of said shaft, and in meshed engagementwith a driven gear 4| rotatably mounted on a vertical stud 42 fixed inthe bed-plate H. The ratio of the gear to the gear 4| is four to onewhich causes the feed-dog to be moved transversely in one direction forone stitch and then transversely in the opposite direction for anotherstitch. The hook shaft 24 is rotated at twice the speed of the mainshaft I4. An adj ustable eccentric 43 has been secured to the lower faceof the gear 4|. A vibratable connection M has been connected at one endto the eccentric 53 by means of a ball-joint. The other end of theconnection M has been connected to the feed-dog carrier 2] by means of aball-joint.

As best shown in Figure 5, I have provided a thread control member 45preferably made of round wire at one end and secured in the base I l bya screw 65. The control member 45 has been flattened at the end underthe feed-dog 22 to clear the hook 23. The feed-dog end of the controlmember 45 has a vertical aperture 41 in alignment with the needle i6 forpassing the needle and bobbin threads therethrough to prevent breakageof the said threads, which would be the case if the said thread controlmember were not used, since the transverse movements of the threads bythe needle plate would cause interference with projecting portions ofthe hook.

Due to the pyramid-shaped teeth 33 at the central portion of thefeed-dog 22, I am able to use a narrow presser-foot 25 and, as shown inFigure 1, one of the feed-dog slots 34 in the needle plate 20 isuncovered by the presser-foot 26. This permits operating very close tothe edge of the fabric worked upon.

The adjustable eccentric 43 comprises a disk 50 having a T-shapedguideway 51 positioned diametrically therein. A T-shaped slide 52 hasbeen mounted in the guideway 51. A screw 53 in threaded engagement inthe slide 52 and freely rotably mounted in a yoke 54 is used to causesliding motion of the member 52 to or from the center of the disk 59. Athreaded aperture 55 in the slide 52 serves to receive a screw 56 havinga ball formation thereon in engagement with the vibratable connection44. The operator may, by adjusting the screw 53, vary the movements ofthe vibratable connection id from zero to maximum, and thus determinethe width of the zigzag stitches.

As shown in Figures 10 and 11, I have provided a modified thread controlmember 58 having a tubular vertical extension 53. The extension 59 has avertically positioned aperture 60 forming a needle-throat which is inalinement with the needle IS. The aperture 60 serves for passing theneedle and bobbin threads therethrough to prevent breakage of the saidthreads due to transverse movements thereof. The tubular extension 59passes through an elongated opening 6| in the work supporting plate 62which is slid'ably mounted in a frame 53. The control member 58 is heldstationary by the screw 46.

It is to be noted that the vertical tubular extension 59 has been madeto terminate at its upper end in line with the top surface of the worksupporting plate, as this prevents any frail fabrics worked upon frombeing drawn below said top surface.

It is also to be noted that while I have shown the drive gear 40 asmounted on the hook driving shaft 24, and the driven gear below thebase, that I may mount the drive and driven gears above the base, andactuate the vibratable rod 44 by suitable connections (not shown) fromone of said gears.

Referring to Figures 12, 13, and 14, it will be noted that I haveprovided a modified zig-zag mechanism 65 comprising a three-sided cam 66having equal arcuate face and being adapted to cause momentary cessationof the transverse motions of the needle-plate at each end of saidtransverse motions. The cam has portions 61 and 68 which are concentricwith the shaft 69. As best shown in Figures 13 and 14, a modifiedvibratable connection 14 has one ball-joint l5 vibratably connected tothe feed-dog carrier 21. At the opposite end of the vibratableconnection 14 is a ball-joint 1B. The shank of the ball on the balljoint16 has a threaded end 11 and a portion 18 having parallel sides adaptedfor sliding motion in an arcuate slot I9 in a yoke 83. The center of thearc of the slot 19 is at the center of the ball-joint 15. A knurled nut8| in threaded engagement with the threaded end 11 serves for securingthe ball-joint 16 in any desired position in the slot 19.

The sliding radial adjustment along the slot 79 provides for increasingor decreasing the throw of the vibratable connection 14 for varyingthewidth of the zig-zag stitching.

As best shown in Figures 13 and 14, the yoke 80 has been pivotallymounted on a stud bolt 82 preferably threaded in the base of the sewingmachine. A bracket 83 secured to the base by a bolt 84 provides abearing 85 for the lower end of the shaft 69.

In accordance with the patent statutes I have described and illustratedthe preferred embodiments of my invention, but it will be understoodthat various changes and modifications can be made therein withoutdeparting from the spirit of the invention as defined by the appendedclaims.

It is to be noted that by vibratable connection is meant any connectionwhich will transmit motion in the six directions herein disclosed, andwhich practically amounts to a universal connection.

As shown in Figure 12, it will be noted that the hook shaft 24 carries abevel gear 86 which meshes with a bevel gear 81 on a vertical shaft 88.The upper end of the shaft 88 carries a bevel 1 gear 89 which mesheswith a bevel gear 9!! carried by the main shaft of the sewing machine.The gears 90 and 89 are of a ratio of two to one. while the gears 81 and86 are of a ratio of one to one. The ratio of the worm gear 48 to thegear 4| is four to one.

I claim:

1. In a sewing machine comprising a bedplate, a hook driving shaft andfeed rock shafts, a feed-dog carrier and feed-dog mounted for slidingmovements on spindles supported in paralllel spaced relation with bothof said rock shafts, said movements being transverse of the line offeeding, a presser-foot supported solely for up-and-down movements, acloth plate having guideways, said cloth plate having a rectangularlyshaped aperture intermediate said guideways, a needle plate slidablymounted in said guideways and having a stud extending downwardlytherefrom and passing freely through said cloth plate aperture, a drivegear mounted on said hook driving shaft and being in meshed engagementwith a driven gear, said driven gear being rotatably mounted on a ver--tical stud fixed in said bedplate, means for converting rotary intoreciprocating motion mounted on said stud, a vibratable connectionhaving ball joints at opposite ends, said vibratable connection beingjoined at one end to said motion converting means, said vibratableconnection being joined at the opposite end to said feed-dog carrier forimparting direct transverse to-and-fro movements from said driven gearto said feed-dog carrier and feed-dog and permitting high speed up anddown as well'as forward and backward andsideways motions of the feed-dogcarrier and feed-dog, said feed-dog carrier having an elongated throughopening and said stud extending into contacting relation with the wallsof said opening, said stud being positioned externally of said feed-dogand serving to connect said needle plate and said feed-dog carrier forsimultaneous to-and-fro movement, when said feed-dog carrier is movedto-and-fro.

2. In a sewing machine comprising a-hook driving shaft and feed rockshafts, a feed-dog carrier and feed-dog mounted for sliding movements onspindles supported in parallel spaced relation with both of said rockshafts transverse of the line of feeding, a cloth plate having guidewaysof dovetail form, said cloth plate having a rectangularly shapedaperture intermediate said guideways, a needle-plate having two beveled,side edges slidably mounted in said guideways and having a studextending downwardly therefrom and passing freely through said clothplate aperture, a drive gear mounted on the hook driving shaft and beingin meshed engagement with a driven gear, said driven gear beingrotatably mounted on a vertical stud fixed in the bedplate, means forconverting rotary into reciproeating motion mounted on said stud, avibratable connection having ball joints at opposite ends, saidvibratable connection being joined at one end to said motion convertingmeans, said vibratable connection being joined at the opposite end tosaid feed-dog carrier for imparting direct transverse to-and-fromovements from said driven gear to said feed-dog carrier and feeddog andpermitting up and down as well as forward and backward and sidewaysmotions of the feed-dog carrier and feed-dog, said feed-dog carrierhaving an elongated through opening and said stud extending intocontacting relation with the walls of said opening, said stud beingpositioned externally of said feed-dog and serving to connect saidneedle plate and said feed-dog carrier for simultaneous to-and-fromovement, when the feed-dog carrier is moved to-and-fro, said feed-doghaving an aperture centrally thereof, and a thread control memberfixedly mounted in alinement with said central aperture means and havinga vertical extension in alignment with the needle, said extensionpassing through said aperture to the upper surface of said needle plate,said extension having a vertical aperture and forming a needle-throatfor passing the needle and bobbin threads therethrough to preventbreakage of said threads during their transverse movements.

3. In a sewing machine comprising a bedplate, a hook driving shaft andfeed rock shafts, a feed-dog carrier and feed-dog mounted for slidingmovements on spindles supported in parallel spaced relation with both ofsaid rock shafts, said movements being transverse of the line offeeding, a presser-foot supported solely for up and down movements, acloth plate having guideways, said cloth plate having a rectangularlyshaped aperture intermediate said guideways, a needle plate slidablymounted in said guideways and having a stud extending downwardlytherefrom and passing freely through said cloth plate aperture, a drivegear mounted on said hook driving shaft and being in meshed engagementwith a driven gear, said driven gear being mounted on a vertical axis insaid bedplate, a rotating member secured to said gear at its lower face,a vibratable connection having ball joints at opposite ends, saidvibratable connection being operatively connected at one end foroperation by said rotating member, said vibratable connection beingjoined at the opposite end to said feed-dog carrier for imparting directtransverse to-and-fro movements from said driven gear to said feed-dogcarrier and feeddog, said vibratable ball-jointed connection beingadapted to permit high speed up and down as well as forward and backwardand sideways motions of the feed-dog carrier and feed-dog, said feed-dogcarrier having an elongated through opening and said stud extending intocontacting relation with the walls of said opening, said stud beingpositioned externally of said feed-dog and serving to connect saidneedle plate and said feed-dog carrier for simultaneous toand-fromovement, when said feed-dog carrier is moved to-and-fro.

4. In a sewing machine comprising a bedplate, a hook driving shaft andfeed rock shafts,-a feeddog carrier and feed-dog mounted for slidingmovements on spindles supported in parallel spaced relation with both ofsaid rock shafts, said movements being transverse of the line offeeding, a presser-foot supported solely for up and down movements, acloth plate having guideways, said cloth plate having a rectangularlyshaped aperture intermediate said guideways, a needle plate slidablymounted in said guideways and having a stud extending downwardlytherefrom and passing freely through said cloth plate aperture, a drivegear mounted on said hook driving shaft and being in meshed engagementwith a driven gear, said driven gear being mounted on a vertical axis insaid bedplate, a cam secured to said gear at its lower face, a yokepivotally mounted below said bedplate and being in engagement with saidcam, a vibratable connection having ball joints at opposite ends, saidvibratable connection being operatively connected at one end to saidyoke, said vibratable connection being joined at the opposite end tosaid feed-dog carrier for imparting direct transverseto-and-fromovements from said driven gear to said feed-dog carrier andfeed-dog, said vibratable ball-jointed connection being adapted topermit high speed up and down as well as forward and backward andsideways motions of the feed-dog carrier and feed-dog, said feeddogcarrier having an elongated through opening and said stud extending intocontacting relation with the walls of said opening, said stud beingpositioned externally of said feed-dog and serving to connect saidneedle plate and said feed-dog carrier for simultaneous to-and-fromovement, when said feed-dog carrier is moved to-and-fro.

5. In a sewing machine comprising a bedplate, a hook driving shaft andfeed rock shafts, a feed-dog carrier and feed-dog mounted for slidingmovements on spindles supported in parallel relation with both of saidrock shafts, said movements being transverse of the line of feeding, acloth plate having guideways, said cloth plate having a rectangularlyshaped aperture intermediate said guideways, a needle plate slidablymounted in said guideways and having a stud extending downwardlytherefrom and passing freely through said cloth plate aperture, a drivegear mounted on said hook driving shaft and being in meshed engagementwith a driven gear, said driven gear being mounted on a vertical axis, acam secured to said gear, a yoke in engagement with said cam, avibratable connection operatively connected at one end to said yoke,said vibratable connection being joined at the opposite end to saidfeed-dog carrier for imparting direct transverse to-and-fro movementsfrom said driven gear to said feed-dog carrier and feed-dog, saidvibratable connection being adapted to permit high speed up and down aswell as forward and backward and sideways motions of the feed-dogcarrier and feed-dog, said feed-dog carrier having an elongated throughopening and. said stud extending into contacting relation with the wallsof said opening, said stud being positioned externally of said feed-dogand serving to connect said needle plate and said feed-dog, carrier forsimultaneous to-and-fro movement, when said feed-dog carrier is movedto-and-fro.

JOSEPH GALKIN.

